User Manual

6–2

Troubleshooting

The VHSC module returns diagnostics in word 1 of the block

transfer read (BTR) to the processor. These codes are identified

below.

Diagnostics Reported in Word 1 of BTR

Word Bit Indication

1 Bit 00

Powerup bit indicates whether a successful BTW with valid data has

occurred since powerup, or since last switched from Program to Run mode.

Bit 0 = 0  Successful BTW

Bit 0 = 1  BTW has not occurred

Bits 0103 Not used

Bits 0407 New data bits. Bit 04 corresponds to counter 0, bit 05 to counter 1, etc.

Bits 0815

Diagnostic byte. This byte is always in BCD format. This byte indicates which

word (164) in the BTW file that was incorrect, or one of the following error

codes. The codes are as follows:

Code

87 Preset or reset illegal for counter 0 with frequency mode

88 Preset or reset illegal for counter 1 with frequency mode

89 Preset or reset illegal for counter 2 with frequency mode

90 Preset or reset illegal for counter 3 with frequency mode

91 Store count illegal for counter 0 with frequency mode

92 Store count illegal for counter 1 with frequency mode

93 Store count illegal for counter 2 with frequency mode

94 Store count illegal for counter 3 with frequency mode

95 Preset greater than rollover for counter 0

96 Preset greater than rollover for counter 1

97 Preset greater than rollover for counter 2

98 Preset greater than rollover for counter 3

BTW length invalid  length not equal to 0, 1, 2, 4, 12, 20, 24, 29,

34, 39, 44, 49, 54, 59, 64.

In this chapter, you learned how to interpret the module indicators,

and the meanimg of the error codes returned by the module.

Diagnostic Codes

Returned by the Module

Chapter Summary